JPS59101653A - Electrophotographic transfer paper - Google Patents

Abstract

PURPOSE:To reduce curling by specifying a ratio of lataral tensile strength to longitudinal one of paper, a ratio of that in the direction at 45 deg. angle to the longitudinal direction to that in the other direction at 45 deg. angle to the longitudinal direction, and the difference of the paper basis weight in the lateral direction. CONSTITUTION:A ratio of lateral tensile strength to longitudinal one Y/T of the paper is set to >=0.4. The difference L-R or R-L between the tensile strengths in the direction inclined left and right at 45 deg. angle to the longitudinal direction L, R is regulated to <=1.0kg, or L/R or R/L is regulated to <=1.25. Scattering of the paper basis weight in the lateral direction within 5cm width is controlled to <=1.5g/m<2>. Consequently, curling in the longitudinal direction of the transfer paper can be reduced, and paper jamming can be prevented in the copying and a sorter.

Description

TECHNICAL FIELD The present invention relates to transfer paper for electrophotography, particularly dry PPC.

Conventional electrophotographic transfer paper tends to curl due to the shrinkage force of the cellulose fibers due to water evaporation due to the heat of the heater, and due to the hardening caused by the passage between the fixing roll and the pressure roll.
There were problems related to errors in the copying machine, uneven copies, sorter errors, and poor running performance when the number of sheets stored in the sorter decreased.

Therefore, in order to stabilize the copying workability (travelability), various proposals have been made to improve stability against curling, especially during heating.

For example, the tension, moisture content, electrical resistance, etc. are set within a certain range.

Such transfer paper has almost no curling after copying in areas other than the edges, which correspond to most of the IJ direction, and has satisfactory running performance. ear (50cm on one side, about 1cm on both ears)
Transfer paper using a portion corresponding to 0.00 cm) has a large curl after copying, and there are cases where diagonal curl occurs in which the diagonal corners of the transfer paper are larger than other corners. However, it is still not sufficient to meet various demands such as increasing the copying speed, double-sided copying, and the use of a sorter.

Purpose: When used in an electrophotographic device (dry type RPC copying machine) with a heat-fixed neck, the curl of the copy paper is small,
To obtain a transfer paper which is improved in drawbacks such as uneven copies, sorter jam, and reduction in the number of sheets stored in a sorter.

Structure The present invention is an electrophotographic transfer paper characterized by having the following characteristics (in to 3).

(b) The ratio (Y/'T) of the tensile strength in the cross-grain direction of the paper (Y) and the tensile strength in the longitudinal direction of the paper (T) is 0.4 or more.
.

(b) Tensile strength in the direction of 45° to the left of the paper grain [)
and the tensile strength R> in the right 45° direction (L-R or R-1> is 1.0 kg or less or L'/R or R/
L is 1.25 or less.

(I＼) Lateral grain direction of paper 5 The tsubo difference within the width of CT11 is 1.
59/Tl12 or less.

As a result of various researches, it has been found that in copying machines and sorters, curls (diagonal curls) in which the corners of the paper are raised, leading to paper jams, are often found. It was found that such substances were especially common in the edges of papermaking base paper.

Therefore, in the present invention, it has been discovered that in order to mainly prevent and cover such curling, it is sufficient to add the above-mentioned requirements a'1 (a) to 3\) by -1. Each requirement is explained below.

(About In, this is an index that shows the ratio of fibers oriented in the slight force direction and fibers oriented in the machine direction. Culm fibers close to 1 are oriented in the same direction and are oriented in the J3 direction, and conversely in the O direction.) The closer it is, the more fibers are aligned in the vertical direction.If Y/T is less than 0.4, there are many m strings oriented in the vertical direction, the vertical curl becomes more than iomm, and a running ↑" defect occurs. In addition, the lateral stiffness decreases, causing poor running, especially in high humidity.

When Y/1- is large, for example 0.6 or more, there is a high probability that the fibers will be oriented diagonally in the normal papermaking process, and there is a high risk of diagonal curling; If the conditions of CI) are satisfied, there is no problem even if Y/T is large.

Regarding (b), it is a parameter of whether or not the pulp fibers are oriented symmetrically with respect to the grain. This shows that the vA fiber orientation is not symmetrical, that is, it is biased to the left or right, and the fibers are aligned diagonally when synthesized.Specifically, the former is 1, Okg If the latter is larger than 1.25, the curl after copying will be 10 mm or more, resulting in poor runnability.

Regarding (c), even if the above conditions (a) and (b) are satisfied, the curl may become large after copying, but as a result of investigating the cause, it was found that under the limited heating conditions of fixing [1 (Mass) (It was found that when there is this step, there is a difference in the heat received m per paper mass, which changes the amount of paper shrinkage, that is, the size of curl. From this point of view, the permissible basis weight variation is the width of the paper. Direction 5C
II111] is 1.5 (1/ +u' or less, and if it exceeds this, the curl after copying (vertical curl or diagonal curl) will be 10 mm or more, resulting in poor running.The transfer paper of the present invention In order to obtain the above-mentioned characteristics, the processing conditions, such as stock supply (G), screen running speed, bleed (m), chain gutter, angle, pressure, etc. of the Nordeckel shower can be appropriately selected.

Next is real 7Il! ! Examples and comparative examples will be explained.

Example 1 and Comparative Example 1.2 Beating degree 500CS F (7) L B K P 10
Using 0% (7) C/Lz7, the internal additions are rosin size 1.0%, sulfuric acid band 1.8%, oxidized starch as a surface sizing agent, and KCI at a ratio of O-5 (J/i11'). A fourdrinier paper machine was used to make paper with a papermaking speed of 400 m/min (tsubo ff 169 g/wa 2). , made 1'2J
Table 1 shows the numerical values of the conditions (a), (b), and (l\) as well as other physical properties.

In addition, a paper with lff1l-composition and three physical properties is also listed in Table 1 as Comparative Example 1.2.

Worry.

Lick 8 Kasa & Neck 3 State Minister
. . .

Gaki -- m Old Old Using each of the above papers, copy machine (product name FT-150
0, manufactured by Ricoh Co., Ltd.) J5 and sorter ~ (product name CS
2020, drivability test 1 by Ricoh Co., Ltd.)
I went to bed. The results are shown in Table 2.

Table 2 Note: O... Good (no problem at all) △
・・・・・・ Bad (usable) × ・・・・
...Unusable Example 2 and Comparative Example 3 A base paper with a basis weight of 64 Q/Tn2 was made in the same manner as in Example 1 except that only oxidized starch was used as the surface 11izing agent with a freeness of 480 CS F. did. The numerical values of the above conditions (A), elongation), Q\) and other physical properties of the product are shown in Table 3.

In addition, paper with the same composition but different physical properties is listed as Comparative Example 3 in Table 3 (ff).

Row training Den mo 0' = I 2 N on I mpac
t Pri+1ter) used as paper, page printer (product name N 7384-21, manufactured by NEC Corporation)
Tested by. The results are shown in Table 4.

Table 4 Note: Slope value... Ratio effect of misalignment width and height when paper is stacked after copying.Ki-ni 1! According to II, the curl after copying J3 on the dry RPC copying machine is within ±10 mm, and the copy fXI J3
d3 G-J to the sorter and d3 G-J degree 17 has decreased, and almost all of them are O. Also, when using continuous paper, mark 1
The (su゛1 slope value) of folded paper after 6+1 has been improved.

Patent 5'1 applicant: Ricoh Co., Ltd. Agent: Patent Attorney: Ji Komatsu

Claims (1)

[Claims] (1) An electrophotographic transfer paper characterized by having the following characteristics (a) to e\). (B) The ratio (Y/”r) of the tensile strength in the horizontal grain direction of the paper (Y) and the tensile strength in the vertical grain direction (T) is 0.4 or more. (0) 45° left direction with respect to the longitudinal grain of the paper The difference between the tensile strength (combined) and the tensile strength (R) in the right 45° direction (L-R or R-L) is 1.0 kg or less or L / R
Or R/L is 1.25 or less. e\) The difference in basis weight within 5 cm width in the horizontal grain direction of the paper is 1.59
/ 1n' or less.